Hope rises as mice regrow organs
(China Daily/The Times )
Updated: 2005-08-30 06:12

"When we injected foetal liver cells taken from those animals into ordinary mice, they too gained the power of regeneration. We found this persisted even six months after the injection."

Heber-Katz made her discovery when she noticed that the identification holes that scientists punch in the ears of experimental mice healed without any signs of scarring.

The self-healing mice, from a strain known as MRL, were then subjected to a series of surgical procedures. In one the mice had their toes amputated - but the digits grew back, complete with joints.

In another test some of the tail was cut off but also regenerated. Then the researchers used a cryoprobe to freeze parts of the animals' hearts, only to see these grow back again. A similar phenomenon was observed when the optic nerve was severed and the liver partially destroyed.

Heber-Katz will describe some of her findings at the Cambridge conference and plans to publish her results in a research paper. "We have found that the MRL mouse seems to have a higher rate of cell division," she said. "Its cells live and die faster and get replaced faster. That seems to be linked to the ability to regenerate."

The researchers suspect that the same genes could confer greater longevity and are measuring the animals' survival rate. The mice are, however, only 18 months old and the normal lifespan is two years so it is too early to reach conclusions.

Scientists have long known that less complex creatures have an impressive ability to regenerate. Many fish and amphibians can regrow internal organs or even whole limbs.